1. Field of the Invention
The present invention relates to a ski shoe or boot composed of a calf and shell base molded out of rigid plastic material substantially surrounding the foot, having a sole underneath. The upper portion of the zone surrounding the heel and the malleoli is provided with journal means allowing for the pivoting of the calf relative to the base shell.
Description of Prior Art
Ski boots of different shapes and configurations are known which operate based upon different principles so as to be relatively rigid, and which provide good comfort and technical characteristics. More particularly, with respect to the flexional control of the calves of ski boots, various possible solutions are known which rely upon metallic spring blades positioned on both sides of the shoe calf. Examples of such apparatus are described in German Application Nos. 17 85 151, 21 63 622, and 22 05 470. The flexional properties of the calf along the longitudinal axis of the boot are assured by the same lateral rigidification means, i.e., lateral steel spring blades secured, respectively, in the shell base and at the top of the calf.
However, such constructions suffer from various disadvantages. In boots containing metallic spring blades on both sides of the calf the elastic metallic blades serve simultaneously contradictory functions, i.e., to allow elastic deformation in the longitudinal direction, and to provide rigidification in the direction transverse to the calf. When it is desired to modify one of these functions, such modification is always achieved to the expense of the other by virtue of the metallic structure of these lateral blades. Furthermore, the insertion of metal in the lateral walls of the calf leads to a much heavier boot construction, which necessitate more complicated molds, and which are, therefore, more costly.
Finally, it is noted that such boots permit only an inappropriate angular displacement in flexion, since these blades are rigidly anchored in the journal zone of the malleoli, while the flexible journal of the calf is positioned above the malleoli in the zone of the shin, corresponding to the lower portion of the peroneal tibia segments, which considerably detracts from the wearing comfort of such boots.
Boots are also known of the type described in French Pat. No. 2,063,622, which rely upon lateral metallic reinforcements provided with journals generally at the level of the malleoli; the journals being themselves linked by spiral springs assuring the elastic connection so as to guarantee the flexion between the top of the calf and the shell base.
As to this latter type of construction, it should be noted that it does attempt to overcome the disadvantages of the boots of the prior art, whose lateral security of the ankles necessarily results in a reduction of the possible flexion of the calf. However, this solution of the prior art suffers from various other inconveniences. In effect, the solution of providing lateral reinforcement journals allowing for frontward flexion results in a complexity of assembly of the boot which is increased by added apparatus assuring the elastic return of the calf after flexion. This complexity of design renders the assembly of such boots costly. Furthermore, the combination of the rigidification and elastic deformation functions at the level of the journalled reinforcement alone affects the reliability and even the strength of the device. Finally, this type of construction, where the reinforcements are embedded in the walls of the shell themselves, adds weight which affects the comfort of the ski boot, which is already strongly compromised by the very nature of this type of boot.